ARMORED CABLE

70-225 B. Installation 333-7. Support. Type AC cable shall be secured by approved staples, straps, hangers, or similar fittings so designed and installed as not to damage the cable at intervals not exceeding 4½ feet (1.37 m) and within 12 inches (305 mm) of every outlet box, junction box, cabinet or fitting. Exception No. 1: Where cable is fished. Exception No. 2: Lengths of not more than 2 feet (610 mm) at terminals where flexibility is necessary. Exception No. 3: Lengths of not more than 6 feet (1.83 m) from an outlet for connections within an accessible ceiling to lighting fixtures or equipment. Exception No. 4: Where installed in cable trays, Type AC cable shall comply with Section 318-8(b). 333-8. Bending Radius. All bends shall be made so that the cable will not be damaged, and the radius of the curve of the inner edge of any bend shall not be less than five times the diameter of the Type AC cable. 333-9. Boxes and Fittings. At all points where the armor of AC cable terminates, a fitting shall be provided to protect wires from abrasion, unless the design of the outlet boxes or fittings is such as to afford equivalent protection, and, in addition, an approved insulating bushing or its equivalent approved protection shall be provided between the conductors and the armor. The connector or clamp by which the Type AC cable is fastened to boxes or cabinets shall be of such design that the insulating bushing or its equivalent will be visible for inspection. This bushing shall not be required with lead-covered cables where so installed that the lead sheath will be visible for inspection. Where change is made from Type AC cable to other cable or raceway wiring methods, a box, fitting, or conduit body shall be installed at junction points as required in Section 300-15. 333-10. Through or Parallel to Framing Members. Type AC cable shall comply with Section 300-4 where installed through or parallel to studs, joists, rafters, or similar wood or metal members. 333-11. Exposed Work. Exposed runs of cable shall closely follow the surface of the building finish or of running boards. Exception No. 1: Lengths of not more than 24 inches (610 mm) at terminals where flexibility is necessary. Exception No. 2: On the underside of floor joists in basements where supported at each joist and so located as not to be subject to physical damage. Exception No. 3: Lengths of not more than 6 feet (1.83 m) from an outlet for connection within an accessible ceiling to lighting fixtures or other equipment. 70-226 NATIONAL ELECTRICAL CODE 333-12. In Accessible Attics. Type AC cables in accessible attics or roof spaces shall be installed as specified in (a) and (b) below. (a) Where Run Across the Top of Floor Joists. Where run across the top of floor joists, or within 7 feet (2.13 m) of floor or floor joists across the face of rafters or studding, in attics and roof spaces that are accessible, the cable shall be protected by substantial guard strips that are at least as high as the cable. Where this space is not accessible by permanent stairs or ladders, protection shall only be required within 6 feet (1.83 m) of the nearest edge of the scuttle hole or attic entrance. (b) Cable Installed Parallel to Framing Members. Where the cable is installed parallel to the sides of rafters, studs, or floor joists, neither guard strips nor running boards shall be required, and the installation shall also comply with Section 300-4(d). C. Construction Specifications 333-19. Construction. Type AC cable shall have an armor of flexible metal tape. The insulated conductors shall be in accordance with Section 333-20. Cables of the AC type shall have an internal bonding strip of copper or aluminum in intimate contact with the armor for its entire length. 333-20. Conductors. Insulated conductors shall be of a type listed in Table 310-13 or those identified for use in this cable. In addition, the conductors shall have an overall moisture-resistant and fire retardant fibrous covering. For Type ACT, a moisture-resistant fibrous covering shall be required only on the individual conductors. The ampacity shall be determined by Section 310-15. Exception: Armored cable installed in thermal insulation shall have conductors rated at 90°C (194°F). The ampacity of cable installed in these applications shall be that of 60°C (140°F) conductors. 333-21. Grounding. Type AC cable shall provide an adequate path for equipment grounding as required by Section 250-51. 333-22. Marking. The provisions of Section 310-11 shall apply, except that Type AC cable shall have ready identification of the manufacturer by distinctive external markings on the cable sheath throughout its entire length. Cables that are flame-retardant and have limited-smoke characteristics shall be permitted to be identified with the suffix LS.